BACKGROUND: Although BCG has been found to impart protection against leprosy in many populations, the utility of repeat or booster BCG vaccinations is still unclear. When a policy of giving a second BCG dose to school children in Brazil was introduced, a trial was conducted to assess its impact against tuberculosis, and a leprosy component was then undertaken in parallel.
OBJECTIVE: to estimate the protection against leprosy imparted by a second dose of BCG given to schoolchildren.
METHODS AND FINDINGS: This is a cluster randomised community trial, with 6 years and 8 months of follow-up.
STUDY SITE: City of Manaus, Amazon region, a leprosy-endemic area in Brazil.
PARTICIPANTS: 99,770 school children with neonatal BCG (aged 7-14 years at baseline), of whom 42,662 were in the intervention arm (revaccination).
INTERVENTION: BCG given by intradermal injection.
MAIN OUTCOME: Leprosy (all clinical forms).
RESULTS: The incidence rate ratio of leprosy in the intervention over the control arm within the follow-up, in schoolchildren with neonatal BCG, controlled for potential confounders and adjusted for clustering, was 0.99 (95% confidence interval: 0.68 to 1.45).
CONCLUSIONS/SIGNIFICANCE: There was no evidence of protection conferred by the second dose of BCG vaccination in school children against leprosy during the trial follow-up. These results point to a need to consider the effectiveness of the current policy of BCG vaccination of contacts of leprosy cases in Brazilian Amazon region.
BT - PLoS neglected tropical diseases C1 - http://www.ncbi.nlm.nih.gov/pubmed/18270542?dopt=Abstract DA - 2008 Feb 13 DO - 10.1371/journal.pntd.0000167 IS - 2 J2 - PLoS Negl Trop Dis LA - eng N2 -BACKGROUND: Although BCG has been found to impart protection against leprosy in many populations, the utility of repeat or booster BCG vaccinations is still unclear. When a policy of giving a second BCG dose to school children in Brazil was introduced, a trial was conducted to assess its impact against tuberculosis, and a leprosy component was then undertaken in parallel.
OBJECTIVE: to estimate the protection against leprosy imparted by a second dose of BCG given to schoolchildren.
METHODS AND FINDINGS: This is a cluster randomised community trial, with 6 years and 8 months of follow-up.
STUDY SITE: City of Manaus, Amazon region, a leprosy-endemic area in Brazil.
PARTICIPANTS: 99,770 school children with neonatal BCG (aged 7-14 years at baseline), of whom 42,662 were in the intervention arm (revaccination).
INTERVENTION: BCG given by intradermal injection.
MAIN OUTCOME: Leprosy (all clinical forms).
RESULTS: The incidence rate ratio of leprosy in the intervention over the control arm within the follow-up, in schoolchildren with neonatal BCG, controlled for potential confounders and adjusted for clustering, was 0.99 (95% confidence interval: 0.68 to 1.45).
CONCLUSIONS/SIGNIFICANCE: There was no evidence of protection conferred by the second dose of BCG vaccination in school children against leprosy during the trial follow-up. These results point to a need to consider the effectiveness of the current policy of BCG vaccination of contacts of leprosy cases in Brazilian Amazon region.
PY - 2008 EP - e167 T2 - PLoS neglected tropical diseases TI - BCG revaccination does not protect against leprosy in the Brazilian Amazon: a cluster randomised trial. UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2238709/pdf/pntd.0000167.pdf VL - 2 SN - 1935-2735 ER -